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991.
Partetravirus is a novel defined genus of animal parvoviruses. Here, we first report the genome sequence of porcine partetravirus strain JSNJ62, which is highly prevalent in mainland China. It will help in understanding the epidemiology and molecular characteristics of the porcine partetravirus. 相似文献
992.
The study of all endogenously produced metabolites, known as metabolomics, is the youngest of the "omics" sciences. It is becoming increasingly clear that, of all of the "omics" techniques, metabolomic approaches will become increasingly useful in disease diagnosis and have potential power to improve our understanding of the underlying mechanisms of cancer. The primary aim of the review is to discuss the relationship between metabolomics and tumors are elucidated in detail. Then the review is also to introduce the technologies of metabolomics, especially emphasizing the application of metabolomics in the fields of oncology. 相似文献
993.
Heat shock protein 90 (HSP90) is an abundant and highly conserved molecular chaperone, playing important roles in multiple
cellular stress responses. The full-length cDNA of planarian Dugesia japonica Hsp90 (designated DjHsp90) was firstly cloned using rapid amplification of cDNA ends (RACE) techniques. It is 2,354 bp, including
an open reading frame (ORF) of 2,148 bp encoding a polypeptide of 715 amino acids with all five HSP90 family signatures. We
sequenced the ORF sequences from genomic DNA, and found only one intron (48 bp) existed in Djhsp90 gene structure. We used western blot and immunohistochemistry to analyze the expression pattern of DjHsp90 in response to
heavy metal exposure and thermal stress at the protein level. Our results show that low doses of heavy metals and elevated
culture temperature induced, but high doses of heavy metals and severe heat shock inhibited DjHsp90 expression. In response
to heavy metals and thermal stress, DjHsp90-positive cells only appeared in the parenchymal tissue under epidermis cells along
the bilateral from head to tail. These positive cells are presumably sensor cells that can detect external environment changes.
Our work provides basic data for the study of stress responses in planarians. 相似文献
994.
We report a pyrosequencing method for detecting a short amelogenin fragment to aid the gender identification. The PCR products
(44/45 bp), including primers and target sequence (4/5 bp) consisting of three point mutations and one indel mutation, were
sequenced by the pyrosequencing method. 100 randomly chosen DNA samples of healthy donors were analyzed with this method,
and all of them were correctly typed. The sensitivity of the technique was 0.5 ng template DNA. No specific peak was found
in any detected animals or organisms except for monkey. For blood samples that were left outside for 26 weeks and DNA degraded
artificially by digesting with DNaseI, this method gave more accurate results than the conventional method. Moreover, four
bone samples analyzed using the method gave clear pyrograph. This method is easy, quick, cheap and suitable for high-throughput
analysis, especially for identifying the gender of highly-degraded DNA samples. 相似文献
995.
Accumulating evidence suggests that inflammatory process may play a role in bladder carcinogenesis. However, the exact mechanisms
of how the inflammatory factors associate with bladder cancer risk are still unknown. In this study, we explored whether polymorphisms
(i.e. IL-4 C-590T, IL-4R Ile50Val, IL-4R Ser478Pro, IL-4R Gln551Arg, IL-13 C-1055T and IL-13 Arg130Gln) of IL-4, IL-4R and IL-13 genes predicted Chinese bladder cancer risk in 817 bladder cancer and 1,141 controls. Genotyping was performed by using the
TaqMan method. We did not find any overall association between these single nucleotide polymorphisms (SNPs) and bladder cancer
susceptibility in a Chinese population. However, in the classification and regression tree (CART) analysis, we found that
carriers of IL-13 C-1055T variant genotype in smokers had a 2.57-fold increased bladder cancer risk with a 55% patient rate (OR = 2.57; 95%
CI = 1.93-3.43), comparing with non-smokers. Similar result was also observed in combination of IL-13 C-1055T and IL-13 Arg130Gln in smokers. By multifactor dimensionality reduction (MDR) analysis, the best interaction model was the two-factor
model that smokers with the IL-13 C-1055T genotypes were the subgroup to predict bladder cancer risk. The results suggested that the genetic variants in IL-4, IL-4R and IL-13 genes might modulate the bladder cancer risk in a Chinese population. 相似文献
996.
Wang F Ma YL Zhang P Yang JJ Chen HQ Liu ZH Peng JY Zhou YK Qin HL 《Molecular biology reports》2012,39(1):269-275
MicroRNAs (miRNAs) are small non-coding RNA molecules that function as negative regulators of gene expression. Common genetic
variants (single nucleotide polymorphisms, SNPs) in miRNA genes may alter their expression or maturation resulting in varied
functional consequences. Until now, several studies had evaluated the association between the polymorphisms in the hsa-miR-196a2
rs11614913 and cancer risk in diverse populations and in multiple types of cancer, with contradictory outcomes. Therefore,
here we performed a meta-analysis to address the association between this polymorphism and cancer risk. A total of nine studies
involving 6,540 cases and 7,562 controls were retrieved based on PubMed. Our analysis demonstrated that hsa-miR-196a2 rs11614913
CC genotype significantly increased the cancer risk in homozygote comparison model compared to TT genotype (OR = 1.18; 95%
CI, 1.01–1.68). Moreover, significant association of this polymorphism with breast cancer was found based on homozygote comparison
model (OR = 1.30; 95% CI, 1.01–1.26) and dominant model (OR = 1.11; 95% CI, 1.01–1.23). In addition, hsa-miR-196a2 rs11614913
CC genotype was significantly associated with cancer risk in Chinese and Indian (OR = 1.21; 95% CI, 1.05–1.40), but not in
Caucasians (OR = 1.03; 95% CI, 0.89–1.19). Taken together, our results indicate that the polymorphism of hsa-miR-196a2 rs11614913
is associated with cancer susceptibility, especially with breast cancer and in Chinese and Indian populations. 相似文献
997.
Tolnai J Szabari MV Albu G Maár BA Parameswaran H Bartolák-Suki E Suki B Hantos Z 《Journal of applied physiology (Bethesda, Md. : 1985)》2012,112(11):1932-1939
The aim of this study was to evaluate airway structure-function relations in elastase-induced emphysema in rats. Sprague-Dawley rats were treated intratracheally with 50 IU porcine pancreatic elastase (PPE, n = 8) or saline (controls, n = 6). Six weeks later, lung volumes [functional residual capacity (FRC), residual volume (RV), and total lung capacity (TLC)] and low-frequency impedance parameters (Newtonian resistance, R(N); tissue damping; tissue elastance, H) were measured, and tracheal sounds were recorded during slow inflation to TLC following in vivo degassing. The lungs were fixed and stained for standard morphometry, elastin, and collagen. In the PPE group, FRC and RV were higher [4.53 ± 0.7 (SD) vs. 3.28 ± 0.45 ml; P = 0.003 and 1.06 ± 0.35 vs. 0.69 ± 0.18 ml; P = 0.036, respectively], and H was smaller in the PPE-treated rats than in the controls (1,344 ± 216 vs. 2,178 ± 305 cmH(2)O/l; P < 0.001), whereas there was no difference in R(N). The average number of crackles per inflation was similar in the two groups; however, the crackle size distributions were different and the lower knee of the pressure-volume curves was higher in the PPE group. Microscopic images revealed different alveolar size distributions but similar bronchial diameters in the two groups. The treatment caused a slight but significant decrease in the numbers of alveolar attachments, no difference in elastin and slightly increased mean level and heterogeneity of collagen in the bronchial walls. These results suggest that tissue destruction did not affect the conventionally assessed airway resistance in this emphysema model, whereas the alterations in the recruitment dynamics can be an early manifestation of impaired airway function. 相似文献
998.
Flow cytometry (FCM) is efficient in detecting both abundance and optical physiological parameters including cell size and cellular carbon content—side scatter (SSC), carotenoids—green and orange fluorescence (FL1 and FL2), and red fluorescence—chlorophylls (FL3) can be obtained by FCM. The utilization of these physiological parameters in indicating water masses in Prydz Bay was investigated for the first time. Picophytoplankton were very sensitive to hydrophysical changes and present distinct characteristics of water masses: Picophytoplankton in water closer to the Amery Ice Shelf were more affected by salinity than by temperature, while temperature became more important than salinity the nearer the picophytoplankton were to the deep sea. The picophytoplankton dealt with declines in light by increasing the size of cells, which increase the fixation of carbon. This can also be increased by high temperature and salinity. Pure water masses can increase the content of chlorophylls and cellular carbon. Generally, the distributions of all the five parameters at upper water depths were less affected by temperature and salinity than by water masses; and these parameters can be as indicators to Summer Surface Water (SSW), Winter Water (WW) and Continental Shelf Water (CSW). 相似文献
999.
LadA, a monooxygenase catalyzing the oxidation of n-alkanes to 1-alkanols, is the key enzyme for the degradation of long-chain alkanes (C15–C36) in Geobacillus thermodenitrificans NG80-2. In this study, random- and site-directed mutagenesis were performed to enhance the activity of the enzyme. By screening
7,500 clones from random-mutant libraries for enhanced hexadecane hydroxylation activity, three mutants were obtained: A102D,
L320V, and F146C/N376I. By performing saturation site-directed mutagenesis at the 102, 320, 146, and 376 sites, six more mutants
(A102E, L320A, F146Q/N376I, F146E/N376I, F146R/N376I, and F146N/N376I) were generated. Kinetic studies showed that the hydroxylation
activity of purified LadA mutants on hexadecane was 2–3.4-fold higher than that of the wild-type enzyme, with the activity
of F146N/N376I being the highest. Effects of the mutations on optimum temperature, pH, and heat stability of LadA were also
investigated. A complementary study showed that Pseudomonas fluorescens KOB2Δ1 strains expressing the LadA mutants grew more rapidly with hexadecane than the strain expressing wild-type LadA, confirming
the enhanced activity of LadA mutants in vivo. Structural changes resulting from the mutations were analyzed and the correlation between structural changes and enzyme
activity was discussed. The mutants generated in this study are potentially useful for the treatment of environmental oil
pollution and in other bioconversion processes. 相似文献
1000.
Haruhiro Higashida Shigeru Yokoyama Jian-Jun Huang Li Liu Wen-Jie Ma Shirin Akther Chiharu Higashida Mitsuru Kikuchi Yoshio Minabe Toshio Munesue 《Neurochemistry international》2012,61(6):828-838
Previously, we demonstrated that CD38, a transmembrane protein with ADP-ribosyl cyclase activity, plays a critical role in mouse social behavior by regulating the release of oxytocin (OXT), which is essential for mutual recognition. When CD38 was disrupted, social amnesia was observed in Cd38 knockout mice. The autism spectrum disorders (ASDs), characterized by defects in reciprocal social interaction and communication, occur either sporadically or in a familial pattern. However, the etiology of ASDs remains largely unknown. Therefore, the theoretical basis for pharmacological treatments has not been established. Hence, there is a rationale for investigating single nucleotide polymorphisms (SNPs) in the human CD38 gene in ASD subjects. We found several SNPs in this gene. The SNP rs3796863 (C > A) was associated with high-functioning autism (HFA) in American samples from the Autism Gene Resource Exchange. Although this finding was partially confirmed in low-functioning autism subjects in Israel, it has not been replicated in Japanese HFA subjects. The second SNP of interest, rs1800561 (4693C > T), leads to the substitution of an arginine (R) at codon 140 by tryptophan (W; R140W) in CD38. This mutation was found in four probands of ASD and in family members of three pedigrees with variable levels of ASD or ASD traits. The plasma levels of OXT in ASD subjects with the R140W allele were lower than those in ASD subjects lacking this allele. The OXT levels were unchanged in healthy subjects with or without this mutation. One proband with the R140W allele receiving intranasal OXT for approximately 3 years showed improvement in areas of social approach, eye contact and communication behaviors, emotion, irritability, and aggression. Five other ASD subjects with mental deficits received nasal OXT for various periods; three subjects showed improved symptoms, while two showed little or no effect. These results suggest that SNPs in CD38 may be possible risk factors for ASD by abrogating OXT function and that some ASD subjects can be treated with OXT in preliminary clinical trials. 相似文献